Compression device with removable portion

ABSTRACT

A device for applying compression treatment to a part of a wearer&#39;s body comprises first and second inflatable bladders spaced apart from one another along an axis of the device. A line of weakness in a connecting section between the first and second bladders extends generally transverse to the axis of the device for selectively separating the inflatable bladders from one another. The device includes an overlying layer in generally opposing relationship to one of the first and second bladder layers. The overlying layer is discontinuous generally adjacent to the line of weakness to define terminal edge margins of the overlying layer extending generally along the line of weakness. Each of the terminal edge margins are connected to at least one of the first and second bladder layers on an opposite side of the line of weakness from the other terminal edge margin.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to co-assigned U.S. application Ser. Nos.11/733,095; 11/733,074; 11/733,084; 11/733,088; 11/733,077; 11/733,082;11/733,087; 11/733,101, each of which was filed on Apr. 9, 2007, andSer. No. 12/098,884, filed on Apr. 7, 2008, the disclosures of which areincorporated herein by reference.

FIELD OF THE INVENTION

The present invention is directed generally to a compression device forapplying compression therapy to a body part of a wearer, moreparticularly a compression device with a removable portion.

BACKGROUND OF THE INVENTION

A major concern for immobile patients and persons alike are medicalconditions that form clots in the blood, such as, deep vein thrombosis(DVT) and peripheral edema. Such patients and persons include thoseundergoing surgery, anesthesia, extended periods of bed rest, etc. Theseblood clotting conditions generally occur in the deep veins of the lowerextremities and/or pelvis. These veins, such as the iliac, femoral,popiteal and tibial return deoxygenated to the heart. For example, whenblood circulation in these veins is retarded due to illness, injury orinactivity, there is a tendency for blood to accumulate or pool. Astatic pool of blood is ideal for clot formations. A major riskassociated with this condition is interference with cardiovascularcirculation. Most seriously, a fragment of the blood clot can breakloose and migrate. A pulmonary emboli can form blocking a main pulmonaryartery, which may be life threatening.

The conditions and resulting risks associated with patient immobilitymay be controlled or alleviated by applying intermittent pressure to apatient's limb, such as, for example, a leg to assist in bloodcirculation. Known devices have been employed to assist in bloodcirculation, such as, one piece pads and compression boots. See, forexample, U.S. Pat. Nos. 6,290,662 and 6,494,852.

For example, sequential compression devices have been used, whichconsist of an air pump connected to a disposable wraparound pad by aseries of air tubes. The wraparound pad is placed around the patient'sleg. Air is then forced into different parts of the wraparound pad insequence, creating pressure around the calves and improving venousreturn.

These known devices may suffer from various drawbacks due to their bulkand cumbersome nature of use. These drawbacks reduce comfort, complianceand may disadvantageously prevent mobility of the patient as recoveryprogresses after surgery.

Therefore, it would be desirable to overcome the disadvantages anddrawbacks of the prior art with a prophylaxis sequential compressiondevice that reduces bulk and is not cumbersome during use to improvecomfort and compliance to a patient. It would be desirable if theprophylaxis sequential compression device includes a removable portionto achieve the advantages of the present disclosure. A compressionsleeve having a removable thigh section is disclosed in co-assigned U.S.patent application Ser. No. 10/784,607, filed Feb. 24, 2004, and thedisclosure of this application is incorporated herein by reference. Thethigh section can be removed by tearing the compression sleeve along aperforation provided in the bladder material. However, this applicationdoes not address issues associated with tearing to multiple layers ofdiffering composition to disconnect a section of the compression device.

SUMMARY OF THE INVENTION

In one aspect, a device for applying compression treatment to a part ofa wearer's body generally comprises first and second opposing bladderlayers secured to one another along two bladder lines to define firstand second inflatable bladders spaced apart from one another along anaxis of the device. A connecting section including a portion of at leastone of the first and second bladder layers extends between andconnecting the first and second inflatable bladders to one another. Aline of weakness in the connecting section extends generally transverseto the axis of the device for selectively separating the inflatablebladders from one another. An overlying layer is in generally opposingrelationship to one of the first and second bladder layers. Theoverlying layer is discontinuous generally adjacent to the line ofweakness to define terminal edge margins of the overlying layerextending generally along the line of weakness. The terminal edgemargins each are connected to at least one of the first and secondbladder layers on an opposite side of the line of weakness from theother terminal edge margin.

In another aspect, a method of making a compression device generallycomprises securing first and second opposing bladder layers to oneanother along two bladder lines to define first and second inflatablebladders spaced apart from one another along an axis of the device andhaving a connecting section extending between and connecting the firstand second inflatable bladders to one another. A line of weakness isformed in the connecting section extending generally transverse to theaxis of the device for selectively separating the inflatable bladdersfrom one another. An overlying layer is secured in generally opposingrelationship to one of the first and second bladder layers. Theoverlying layer is discontinuous generally adjacent to the line ofweakness to define opposing terminal edge margins. Each of the terminaledge margins is secured to one of the first and second bladder layers ona respective opposite side of the line of weakness.

Other features will be in part apparent and in part pointed outhereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation of one embodiment of a compression sleevewith an outer cover and bladder layers of the sleeve partially removedto show underlying layers;

FIG. 2 is an exploded perspective of the compression sleeve;

FIG. 2A is an enlarged, fragmentary view of FIG. 1 showing a perforationline extending across a left bridge of the compression sleeve;

FIG. 2B is similar to FIG. 2A with the perforation line comprisingcircular openings;

FIG. 2C is similar to FIG. 2A with the perforation line comprisingslot-shaped openings;

FIG. 2D is a section taken in the plane including line 2D-2D in FIG. 2A;

FIG. 2E is an enlarged, fragmentary view of FIG. 1 showing a perforationline extending across a right bridge of the compression sleeve;

FIG. 3 is a rear elevation of an inner layer of the compression sleeve;

FIG. 4 is a front elevation of the compression sleeve with the outercover removed;

FIG. 5 is a longitudinal section of the compression sleeve withinflatable bladders of the sleeve in an inflated state;

FIG. 6 is a longitudinal section of the compression sleeve with theinflatable bladder in a deflated state;

FIG. 7 is an enlarged fragmentary elevation of the outer coverillustrating loop material;

Corresponding reference characters indicate corresponding partsthroughout the drawings.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now to the drawings, and in particular to FIGS. 1 and 2, oneembodiment of a compression device (broadly, “a garment or a sleeve”) isgenerally indicated at 10 for applying sequential compression therapy toa limb of a wearer. The compression sleeve is of the type sized andshaped for being disposed around a leg of the wearer, but could beconfigured for application to other parts of the wearer's body. Morespecifically, the sleeve 10 has a width W (FIG. 1) for being wrappedaround a full circumference of the leg and a length L (FIG. 1) forrunning from the ankle to a thigh of the leg. This type of sleeve isgenerally referred to in the art as a thigh-length sleeve including athigh section 11 a, a calf section 11 b and an ankle section 11 c. Itwill be understood that a compression sleeve may come in differentsizes, such as a knee length sleeve (FIG. 20) that extends from theankle up the calf of the leg. It is understood that other types ofcompression devices for being disposed about other limbs of the wearer'sbody, are within the scope of this invention, such as a wrap around apatient's chest in the treatment of breast cancer.

A numerical study performed by R. D. Kamm, titled “BioengineeringStudies of periodic External Compression as Prophylaxis Against DeepVein Thrombosis—Part I: Numerical Studies” concluded, among otherthings, that “the entire length of the veins should be emptied as fulland as rapidly as possible.” The Kamm study reviews three types ofcompression, the one of interest is wavelike compression. Wavelikecompression is most similar to sequential compression provided by theillustrated embodiments of the present invention. The Kamm Study foundwavelike compression is most effective in moving blood for an effectiveprophylaxis treatment.

Referring to FIG. 1, the compression sleeve 10 comprises four layerssecured together in the illustrated embodiment of the present invention.The scope of the present invention is not limited to four layers. Morespecifically, the compression sleeve comprises an inner layer, generallyindicated at 12, on which a first intermediate layer (broadly, a firstbladder layer), generally indicated at 14, is overlaid. A secondintermediate layer (broadly, a second bladder layer), generallyindicated at 16, overlies the first intermediate layer 14 and is securedthereto. An outer cover generally indicated at 18, overlies and issecured to the second intermediate layer 16. In use, the inner layer 12is disposed most adjacent to the limb of the wearer and is in contactwith the limb of the wearer, and the outer cover 18 is most distant fromthe limb of the wearer. A knee opening 19 is formed through the sleeve10 that is generally aligned with the back of the knee when the sleeveis applied to the leg. The layers have the same geometric shape and aresuperposed on each other so that edges of the layers generally coincide.It is contemplated that one or more of the layers 12, 14, 16, or 18 maynot be superposed on a corresponding layer, but slightly offset toaccommodate a particular feature of a patient's limb. Moreover, thenumber of sheets or thickness making up each layer 12, 14, 16, or 18 ofthe compression sleeve 10 may be other than described. The thickness ofthe layers may vary to add strength or to cause more expansion in onedirection, such toward the limb, during inflation.

Referring to FIGS. 1, 2 and 4, the first and second intermediate layers14, 16, respectively, each include a single sheet of elastic material(broadly, “bladder material”). For example, the sheets 14 and 16 aremade of a pliable PVC material as the bladder material. Layers 12 and 18are made of a polyester material. The second intermediate layer 16 issecured to the first intermediate layer 14 via three separate bladderseam lines 22 a, 22 b, 22 c defining a proximal bladder 24 a, anintermediate bladder 24 b and a distal bladder 24 c, respectively, thatare spaced apart longitudinally along the sleeve 10. The number ofbladders may be other than three without departing from the scope of thepresent invention. As used herein, the terms “proximal”, “distal”, and“intermediate” represent relative locations of components, parts and thelike of the compression sleeve when the sleeve is secured to thewearer's limb. As such, a “proximal” component or the like is disposedmost adjacent to a point of attachment of the wearer's limb to thewearer's torso, a “distal” component is disposed most distant from thepoint of attachment, and an “intermediate” component is disposedgenerally anywhere between the proximal and distal components.

For reasons discussed below, the proximal bladder 24 a defines aproximal, lateral extension 25 near the upper edge margin of the sleeve10. The bladders 24 a, 24 b, 24 c are circumferential bladders meaningthat they are sized and shaped to be wrapped around substantially theentire circumference of the wearer's limb or very nearly the entirecircumference of the limb. For example, in one embodiment the bladders24 a, 24 b, 24 c each extend around at least 90% of a mediancircumference of a leg. However, prior art devices have partial bladderssuch as AirCast® and HillRom®, and these prior art devices do notprovide for openings, elasticity and other features of the presentinvention. It is to be understood that the construction described hereincan be adopted by the prior art sleeves with a partial bladderconstruction, without departing from the scope of the present invention.

The intermediate layers 14, 16 may be secured together by radiofrequencywelding, adhesive, or other chemical and/or mechanical process. It isunderstood that the intermediate layers 14, 16 may be secured togetherat other locations, such as around their peripheries and at bladder seamlines 22 a, 22 b, 22 c to further define the shape of the inflatablebladders 24 a, 24 b, 24 c. For purposes discussed below, the firstintermediate layer 14 is secured to the inner layer 12 along a seam line25 (FIGS. 5 and 6) that runs along the outer periphery of the firstintermediate layer 14 so that central regions of the bladders 24 a, 24b, 24 c are not secured to the inner layer 12. This permits the bladders24 a, 24 b, 24 c to move relative to the inner layer 12. The secondintermediate layer 16 may also be secured to the inner layer 12 alongthe same seam line 25. The first intermediate layer 14 may be secured tothe inner layer 12 by RF welding or adhesive or in other suitable ways.This structure improves comfort as described below.

Referring to FIGS. 2 and 4, each inflatable bladder 24 a, 24 b, 24 creceives fluid from a source of compressed fluid (not shown) via adedicated proximal bladder tube 26 a, intermediate bladder tube 26 b,and distal bladder tube 26 c, respectively, (FIG. 2). A tube line neednot be dedicated to a bladder to practice the invention. Each tube 26 a,26 b, 26 c is disposed between the intermediate layers 14, 16 andsecured to the respective bladder 24 a, 24 b, 24 c by the respectivebladder seam line 22 a, 22 b, 22 c. As shown best in FIGS. 2 and 4, thefirst intermediate layer 16 defines a cutout 27 (FIG. 2) so thatportions of the tubes 26 a, 26 b, 26 c are not disposed between theintermediate layers. Other ways of securing the tubes 26 a, 26 b, and 26c to the bladders 24 a, 24 b, and 24 c are within the scope of theinvention. The opposite ends of the tubes 26 a, 26 b, 26 c are groupedtogether using a second connector 30 (FIGS. 1 and 2) that is adapted tofluidly connect the tubes to the source of compressed fluid. The sourceof compressed fluid may be an air compressor under the control of amicroprocessor that sequentially pressurizes the bladders as isgenerally known in the art. An exemplary air compressor is described inU.S. Pat. No. 5,876,359 to Bock, the disclosure of which is incorporatedherein by reference. The bladders 24 a, 24 b, 24 c may be configured tocontain air pressurized to at least about 10 mm Hg (1333 Pa) to about 45mm Hg (6000 Pa). The bladders should be capable of being repeatedlypressurized without failure. Materials suitable for the sheets include,but are not limited to, flexible PVC material that will not stretchsubstantially. In another embodiment, the intermediate layers may form achamber for receiving an inflatable bladder that is formed separate fromthe chamber. In this embodiment, the layers may not be capable ofcontaining pressurized air as along as the inflatable bladders are socapable. It will be noted that the bladders 24 a, 24 b, 24 c can haveopenings 32 extending completely through the bladders, as described inthe embodiments of the present invention.

Referring particularly to FIGS. 1 and 4, the sleeve 10 defines aconnecting section including a pair of bridge members 84 on oppositesides of the knee opening 19 that extend between and connect a proximalportion of the sleeve that includes the proximal bladder 24 a to theremainder of the sleeve. The proximal tube 26 a generally lies along anaxis of bridge member 84 to provide structural, lengthwise support tothe sleeve 10. As shown best in FIG. 4, the cutout 27 in theintermediate sheet 16 does not extend through the bridge member 84. Theproximal tube 26 a extends between spaced apart distal spot welds 86disposed adjacent to a distal end of the bridge member 84 and betweenspaced apart proximal spot welds 88 disposed adjacent to a proximal endof the bridge member. The spot welds secure the tube 26 a to the bridgemember 84 such that the proximal bladder tube 26 a constitutes a rigidstructural component (broadly, a “first rigid structural component”) formaintaining the spacing between the proximal bladder 24 a and theintermediate bladder 24 b and in maintaining the longitudinallystructural integrity of the connecting section. In other words, thesleeve 10 is rigidified against collapsing or sliding down the wearer'sleg. As explained above, the proximal bladder tube 26 a is secured tothe proximal bladder 24 a at the proximal, lateral extension 25. Theproximal bladder tube 26 a runs along a side of a distal portion of theproximal bladder 24 a so that it does not enter the bladder until itreaches the proximal, lateral extension 25. Being secured at theproximal, lateral extension 25 of the bladder 24 a provides additionallongitudinal support to the sleeve 10 because the proximal bladder tube26 a extends lengthwise across more of the proximal portion of thesleeve than if the tube was secured at a distal portion of the bladder.In one embodiment, the proximal bladder tube 26 a extends at least aquarter of the way across a thigh section of the sleeve 10. In anotherembodiment shown in FIG. 4, the tube 26 a extends more than half wayacross the thigh section. This helps to keep the proximal portion of thesleeve 10 from collapsing and/or sliding out of position down thewearer's leg.

Referring to FIGS. 2 and 4, in addition to the proximal bladder tube 26a, a second rigid structural component 90, disposed between theintermediate layers 14, 16 and extending within the other bridge member84 of the connecting section, also provides longitudinal structuralsupport to the sleeve 10. The second structural component 90 extendsbetween proximal and distal ends of the bridge member 84. The respectiveproximal and distal ends of the structural component 90 are wider thanan intermediate portion of the component and the periphery of thecomponent generally conforms to the peripheries of side walls of thebridge member 84 so that the structural component is secured to thebridge member.

Referring to FIGS. 1, 3 and 4, the proximal bladder 24 a is secured tothe inner layer 12 and the outer cover 18 at spot welds 92 adjacent tothe bladder openings 32 and within an outer perimeter of the bladderdefined by the bladder seamline 22 a. The spot welds 92 maintain theouter cover 18 and the inner layer 12 in proper position with respect tothe bladders 24 a, 24 b, 24 c. In other words, the spot welds 92 preventthe bladders 24 a, 24 b, 24 c from substantially shifting relative tothe inner layer 12 and the outer cover 18 while still providing thesleeve 10 with substantial flexibility. Too much movement of inner layer12 and the outer cover 18 with respect to the bladders 24 a, 24 b, 24 cmay reduce the fit of the sleeve, thereby leading to reduced efficacy ofthe compression therapy. The proximal bladder 24 a is free fromsecurement to the inner layer 12 and outer cover 18 other than at thespot welds 92 to maintain flexibility of the sleeve so that mobility ofthe patient's leg is not compromised. Inner layer 12 may be joined tolayer 16 at the spot welds 86, 88, 92 or the inner layer 12 may bejoined at the seam line 34 of the opening 32. Away from the openings 32and spot welds 86, 88, 92, the inner layer 12 is not joined to surfaceof the bladder material forming the bladder that expands to providecompression treatment to the patient's limb.

In the illustrated embodiment, the thigh section 11 a is removable fromthe remainder of the sleeve 10. In particular, the proximal portion ofthe sleeve 10 that includes the proximal bladder 24 a and the bridgemembers 84 are removable from the remainder of the sleeve. Tear lines(broadly, lines of weakness) comprising perforation lines 93 in theintermediate layers 14, 16, extend transversely across the intermediatelayers adjacent to where the bridge members 84 join thigh section 11 ato the knee and ankle sections 11 b, 11 c. In a preferred embodiment,the removal is destructive and permanent. It is understood that thesleeve may include one tear line or more than two tear lines within thescope of the invention. It is also understood that the shapes of theperforations may be circular (FIG. 2B) or slot-shaped (FIG. 2C) or othershapes within the scope of the invention. Other ways of weakening thesleeve 10 at the tear lines besides the perforation lines 93 are withinthe scope of the present invention. For example, the tear lines mayinclude a thinned out portion of the intermediate layers 14, 16. It isalso understood that the tear lines may be used in other types ofcompression devices other than the illustrated compression sleeve. Forexample, a compression device with two bladders and a compression devicewith more than three bladders are within the scope of the invention.Still further, the tear lines may be positioned to disconnect differentones of the sleeve sections (i.e., besides the thigh section 11 a).

Neither the inner liner 12 nor the outer cover 18 have lines orweakness, although such a configuration is contemplated and within thescope of the present invention. Instead, as shown best in FIGS. 2A and2D, both the inner liner 12 and the outer cover 18 are discontinuousgenerally adjacent to the perforation lines 93 in the intermediatelayers 14, 16 so as to define respective opposing terminal edge margins94 adjacent to the perforation lines. Each perforation line 93 isdisposed between respective opposing terminal edge margins 94 of theinner liner 12 and the outer cover 18. In the illustrated embodiment,the terminal edge margins 94 of the inner liner 12 and the outer cover18 are at least partially welded or otherwise secured to respectiveintermediate layers 14, 16 along terminal securement lines 95 a, 95 bassociated with the respective left and right bridge members 84. Theweld lines 95 a. 95 b are contiguous with the seamline 42 securing thebladder layers 14, 16 to the inner liner 12 and outer cover 18. Each ofthe terminal securement lines 95 b associated with the right bridgemember 84 (FIG. 2E) are continuous and extend across the bridge member.However, the terminal securement lines 95 a that are associated withleft bridge member 84 (FIGS. 2A-2C) are discontinuous and do not extendacross the proximal bladder tube 26 a. Instead, the terminal securementlines 95 a extend part way toward the center of the bridge 84, but turnback and curve down to the end of the terminal edge margins 94. Thesecurement lines 95 a thus form opposed inwardly projecting portions onopposite sides of the bladder tube 26 a and facilitate location of thebladder tube. However, the weld lines 95 a do not permanently join thebladder tube 26 a so that it can be removed, as described hereinafter.

Generally, each terminal edge margin 94 is connected to the intermediatelayers 14, 16 on a respective opposite side of the perforation line 93.By making the inner liner 12 and the outer cover 18 discontinuous atlocations adjacent to the perforation lines 93 in the intermediatelayers 14, 16, the sleeve is more easily torn at the perforation linesthan if the inner liner and the outer cover were continuous and includedperforation lines like the perforation lines in the intermediate layers.Moreover, the sleeve's resistance to tearing is greater at the terminalsecurement lines 95 a, 95 b. This greater tear resistance at theterminal securement lines 95 a, 95 b facilitates more precise tearing ofthe sleeve along the perforation lines 93 and prevents incidental,significant deviation from the tear lines. It is understood that thetear lines may be in other locations other than illustrated for removingthe thigh section 11 a from the remainder of the sleeve 10. Asillustrated, the knee and ankle sections 11 b, 11 c do not have tearlines between them. It is also understood that the sleeve 10 may beconfigured to have other removable portions in addition to or instead ofthe thigh section 11 a within the scope of the present invention.

As described previously, the proximal bladder tube 26 a is disposedbetween the intermediate layers 14, 16 and extends through one of thebridge members 84. The proximal bladder tube 26 a is releasably securedto the connector 30 so that the proximal bladder tube can bedisconnected from the connector and so that the thigh section 11 a canbe removed from the remainder of the sleeve 10. The connector 30 and theproximal bladder tube 26 a may be of the type disclosed in pending U.S.patent application Ser. No. 10/784,607, filed Feb. 23, 2004 and assignedto the assignee of the present application, the entirety of which isherein incorporated by reference. In particular, the connector 30permits non-destructive disconnection of the proximal bladder tube 26 ain preparation for removing the thigh section 11 a. Because the proximalbladder tube 26 a extends through one of the bridge members 84 generallytransverse to the tear line, it may be difficult to tear the sleeve 10along the corresponding perforation lines in the intermediate layers 14,16. Accordingly, a tube access opening or window 96 is formed by anopening 96 a in the outer cover 18 and an aligned opening 96 b in thesecond intermediate layer 16. Because the window extends through theouter cover 18 and the second intermediate layer 16 adjacent to theouter cover to expose a portion of the proximal bladder tube tofacilitate removal of the proximal bladder tube 26 a from the bridgemember 84 before tearing the sleeve 10. In the illustrated embodiment,the tube access window 96 is generally oblong and extends less than thefull axial length of the bridge member 84. In use, the proximal bladdertube 26 a can be disconnected from the connector 30 and then pulledthrough the tube access window 96 so that the tube no longer extendspast the tear line between the intermediate layers 14, 16. With the tube26 a removed from between the intermediate layers 14, 16 at thecorresponding tear line, the sleeve can be easily torn along theperforation lines 93 to remove the proximal portion, including theproximal bladder 24 a, and the bridge members 84.

In one embodiment, the bladders 24 a, 24 b, 24 c are constructed toexpand more toward the wearer than away from the wearer, therebyapplying a greater compressive force on the wearer's limb. In oneexample, the first intermediate layer 14 (i.e., the layer most adjacentto the inner layer 12) has a lesser thickness than that of the secondintermediate layer 16. With both layers 14, 16 being of the samematerial (i.e., elastic PVC material) the first intermediate sheet willhave a lower modulus of elasticity. Thus, when air is introduced intothe bladders 24 a, 24 b, 24 c, the bladders will expand more toward theinner layer 12 and the wearer than away from the wearer. It isunderstood that other ways, besides a difference in thickness betweenthe intermediate layers 14, 16, of constructing the bladders 24 a, 24 b,24 c so that they expand more toward the wearer than away from thewearer is within the scope of the invention.

Referring to FIGS. 2 and 3, the inner layer 12 is constructed of amaterial that is capable of wicking moisture near a patient's limb. Itis understood that the inner liner 12 may be of other configurations,may have other characteristics and properties, and may be formed fromother material than described below. The inner (or “wicking”) layer 12,through capillary action, absorbs moisture trapped near the leg or limbof the wearer, carries the moisture away from the surface of the limb,and transports the moisture from locations on the limb at the innerlayer 12 where the moisture is abundant to areas where it is lessabundant, at the openings 32, for evaporation to the ambientenvironment. The openings may be of various sizes, shapes and locationswithin the bladder area providing the compression. An opening 32 exposesthe wicking layer to the ambient or surrounding air as opposed to theportion of the wicking layer beneath the bladder material. The portionsof the inner layer 12 in registration with the openings 32 may bereferred to as “exposed portions”. Other ways of exposing the wickingmaterial are within the scope of this invention, such as slits orextending the wicking material outside the perimeter of the bladdermaterial. The present invention has its exposed portion within thebladder area that provides compression. The compression region is thebladder area expanding and contracting under the influence of airpressure or other fluids. The area of the bladder not providingcompression is the seamline or weld points which are points of thebladder material sealed together to provide an air or water tightboundary or other regions of the opposed sheets 14, 16 outside theperimeter of the bladder. The wicking material 12 may be inter-weavedwith the impervious material to form the inner layer 12. The wickingmaterial 12 transports moisture to an area of less moisture. Theopenings 32 must be engineered to maintain blood velocity, whilemaximizing evaporation of moisture. Suitable wicking materials may becomprised of, for example, some form of, polyester, although they may becomprised of polypropylene. Microfibers may be used. Suitable microfibermaterials include, but are not limited to, CoolDry model number CD9604,sold by Quanzhou Fulian Warp Knitting Industrial Co., Ltd., QuanzhouCity, Fujian Province, China and CoolMax®, sold by E. I. du Pont deNemours and Company, Wilmington, Del.

The construction of wicking layer, openings, bladder and outer layer isdiscussed. The openings must be sized and shaped to maintain the bloodflow efficacy of a compression sleeve like model 9529 and to provideimproved evaporation of moisture for increasing patient compliance. Forexample and without being limiting, Table 1 (below) illustratesexemplary percentages and open areas of the openings 32 in each of smallknee-length compression sleeves, medium knee-length compression sleeves,medium thigh-length compression sleeves, and large thigh-lengthcompression sleeves. Other percentages and open areas are within thescope of the invention.

TABLE 1 Small Medium Medium Large Knee Knee Thigh Thigh % open area ofbladders* 1.64% 5.97% 9.44% 7.50% % open area of entire sleeve 0.94%3.93% 4.44% 3.35% open area of one aperture 0.247 0.61 0.68-0.880.67-0.86 in²** *all three bladders combined. **thigh length sleeveshave larger apertures in the thigh bladder, therefore a range of sizesis provided.

Referring to FIGS. 1 and 4, the sleeve 10 is constructed so thatportions of the intermediate layers 14, 16 do not overlie the innerlayer 12 so that moisture wicked by the inner layer 12 travels to openportions of the inner layer 12 and evaporates to the atmosphere. In thisillustrated embodiment, each inflatable bladder 24 a, 24 b, 24 cincludes openings 32 that extend through the first and secondintermediate layers 14, 16, respectively, to the inner layer 12. One wayto form such an opening is to seal the intermediate layers 14, 16together within the periphery of the respective bladder 24 a, 24 b, 24 cusing a continuous sealing line 34. The portions of the intermediatelayers 14, 16 within a periphery of the sealing line 34 can be removed,such as by cutting, thereby forming the openings 32. Other ways offorming the openings 32 are within the scope of this invention. Once anopening size and pattern is determined, a metal die is cast to cut theopenings in the PVC bladder material for the opposing sheets.

For the preferred embodiment, the opening shape is generally shaped likea waterdrop. Each opening 32 is tapered from a first round end portiontoward a second, smaller round end portion. The openings 32 may be ofother shapes, such as circles, ovals, and slits, without departing fromthe scope of the invention. The opening shapes may be inter-mixed at thebladder without departing from the scope of the invention

With respect to each bladder 24 a, 24 b, 24 c, the openings 32 arearranged in a distal row 36 and a proximal row 38 (FIG. 4). Both rows36, 38 extend across the respective bladder 24 a, 24 b, 24 c along thewidth W of the sleeve 10. As depicted in the drawings, the openings 32in each proximal row 38 are inverted medium waterdrop-shaped openings inthat the openings taper distally, while the openings in each distal row36 are right-side-up in that the openings taper proximally. The openings32 in each distal row 36 are offset along the width W of the sleeve fromthe openings in the respective proximal row 38. Offsetting the openings32 distributes the openings evenly across the surface area of thebladders 24 a, 24 b, 24 c, thereby increasing the breathability of thebladders and the overall breathability of the sleeve 10 withoutcompromising the structural integrity of the bladders or their abilityto apply compressive force (i.e., prophylaxis treatment) to the leg orbody part. Moreover, offsetting the openings in the respective distaland proximal rows 36, 38, also makes the bladders 34 a, 34 b, 34 c morestretchable in the widthwise direction of the sleeve 10. Other ways ofallowing fluid wicked by the inner layer 12 to evaporate, besides theopenings 32 through the bladders are within the scope of the invention.

Referring to FIGS. 1 and 2, the outer cover 18 of the compression sleeve10 is constructed of a single sheet of material. The outer cover 18 isbreathable and has a multiplicity of openings 40 or perforations so thatit has a mesh construction to provide even more breathability. It isunderstood that the outer cover 18 may be of other configurations, mayhave other characteristics and properties, and may be formed from othermaterial than described below. A suitable material for the outer cover18 may be a polyester mesh. The rate of evaporation from the openings isimproved by treating the fibers of the mesh material with a hydrophilicmaterial. The mesh material will absorb the wicked fluid more readily.Wicking fibers of this type are indicated generally at 21 in FIG. 7.These hydrophilic fibers lower the surface tension of the mesh materialto allow bodily fluids to more easily absorb into the fibers and spreadtherethrough for a more efficient evaporation of the wicked fluid.Absorbing fluid more readily will allow the fluid to move to the openareas more quickly for evaporation. The capillary effect is made moreefficient as the absorbed fluid at the openings is moved more quicklythrough the mesh outer cover 18.

Referring to FIGS. 1, 5 and 6, the outer cover 18 is secured to thesecond intermediate layer 16 along seam line 42, which runs onlyadjacent to the outer periphery of the second intermediate layer so thatthe bladders 24 a, 24 b, 24 c are free from attachment to the cover. Thesecond intermediate layer 16 may be secured to the inner layer 12 by RFwelding or adhesive or in other suitable ways.

Referring to FIGS. 1 and 7, the entirety of an outer surface of theouter cover 18 also acts as a fastening component of a fastening systemfor securing the sleeve 10 to the limb of the wearer. In a particularembodiment, the outer cover 18 of mesh (FIG. 7), for example, has anouter surface comprising loops 44 (FIG. 7) that acts as a loop componentof a hook-and-loop fastening system. A mesh construction, as shown inFIG. 7, has interconnected or weaved fibers 21 of material forming theouter cover 18. The loops 44 may be formed as part of the material ofthe outer cover 18 or otherwise disposed on the surface of the outercover. A suitable material with such construction is a polyester meshloop 2103 sold by Quanzhou Fulian Warp Knitting Industrial Co., Ltd. ofQuanzhou City, China. Hook components 46 (FIG. 3) are attached to aninner surface of the inner layer 12 at the proximal, intermediate anddistal flaps 41 a, 41 b, 41 c, respectively. The loops 44 of the outercover 18 allow the hook components 46 (FIG. 3) to be secured anywherealong the outer surface of the outer cover when the sleeve 10 is wrappedcircumferentially around the limb of the wearer. This allows for sleeve10 to be of a substantially one-size-fits-all configuration with respectto the circumferences of different wearers' limbs. Moreover, the outercover 18 having the loops 44 allows the practitioner to quickly andconfidently secure the sleeve 10 to the wearer's limb without needing toalign the fastening components.

It is contemplated that the outer cover 18 may be capable of wickingfluid in addition to being breathable. For example, the outer cover 18may be constructed of the same material as the inner layer 12 (e.g.,Cool dry). In this way, the moisture wicked by the inner layer 12 may bewicked by the outer cover 18 through the openings 32 in the bladders 24a, 24 b, 24 c. The moisture will then spread out evenly across the outercover 18 and is able to evaporate more readily than if the outer coverwas not formed of a wicking material because a greater surface area ofthe outer cover, as opposed to the inner layer 12, is exposed to air.Alternatively, the cover can have a wicking material laced in or on topof outer layer.

The compression sleeve 10 as a whole is more comfortable to wear becauseof the synergistic relationship of the layers 12, 14, 16, 18. Forexample, the inner layer 12 is capable of wicking moisture from the limband allowing the moisture to evaporate out of the sleeve 10. As statedabove, wicking involves transporting moisture away from the limb andmoving moisture from locations where it is abundant and transporting itto areas where it is less abundant. Material decreases its wicking ratewhen the moisture is equally distributed in the wicking material and thewicking material is saturated. However, the breathability of the sleeve10 allows for the wicked moisture to evaporate. The waterdrop-shapedopenings 32 in the bladders 24 a, 24 b, 24 c and the breathable outercover 18 allow moisture in the inner layer 12 that is adjacent to theopenings to evaporate therethrough. Accordingly, as the moistureevaporates, it is transported to the drier portions of the inner layer12, and the inner layer is able to wick more moisture.

To improve patient mobility, the sleeve was designed to have an elasticinner layer 12 and outer cover 18. An elastic sleeve improves comfortwhich increases patient compliance. Refer to FIGS. 1-7 for thediscussion on elasticity below. An elastic device will conform to apatient's limb to ensure continuous wicking. A compliant orsubstantially conforming fit will help ensure the contact of the bladderagainst a patient's skin during use. The bladder applies the pressure tomove the blood. The elastic outer layer helps reduce number of straps tohold the sleeve in place because the elastic outer layer 18 returns itsoriginal shape exerting a slight force against the patient's limb. Thisforce helps hold the sleeve in place and also allows the practitionernot to over tighten a strap. Some prior art devices use an elasticstocking, such as the T.E.D.® stocking, beneath the compression sleeve.The compression sleeve of at least some embodiments avoids the two stepprocess of first placing the compression stocking on the patient, thenplacing the sleeve over the stocking. Also sleeves of preferredembodiments of the present invention simplify the job of the nursesbecause there is no need to order a stocking and sleeve.

The Applicant devised an elasticity test for determining the amount ofstretch around the limb and along the limb. A patient needs to be mobileduring treatment. Prior art sleeves can be awkward, stiff and heavy sothe user would remove the device, if they needed to move about. The needis to improve elasticity without distorting the openings 32 too muchsuch as becoming elongated or causing an opening to overlie, whichreduces its size for evaporation.

For example, the inner layer 12 is preferably elastically stretchablealong the width W of the sleeve 10 so that the inner layer is able toconform circumferentially to the shape of the wearer's limb. Conformingcircumferentially allows the inner layer 12 to remain in close, intimateand continuous contact with the wearer's limb to ensure that the innerlayer is continuously wicking moisture from the limb. The inner layer 12may also be stretchable the length L. Preferably, the inner layer 12 iselastically stretchable along both the width W and the length L of thesleeve and is more elastically stretchable along the length of thesleeve 10 than along the width. Summarizing the preferred approach,using the test described below, the inner layer 12 may have an averageelasticity in the widthwise direction of the sleeve of between about 13lbs/in (23 N/cm) and about 14 lbs/in (25 N/cm), and in one embodimenthas an elasticity of about 13.3 lbs/in (23.3 N/cm). The inner layer 12may have an average elasticity in the lengthwise direction of the sleeveof between about 0.5 lbs/in (0.9 N/cm) and about 0.7 lbs/in (1.2 N/cm),and in one embodiment has an elasticity of about 0.63 lbs/in (1.10N/cm). The small openings 20 in the inner layer 12 also allow for theinner layer stretch more.

The outer cover 18 is also elastically stretchable along the length L ofthe sleeve 10 or stretchable along both lengthwise and widthwise(circumferentially). Preferably, the outer cover 18 is more elasticlongitudinally than widthwise. Although elastically stretchable, theouter cover 18 acts to restrain the amount of expansion of the bladders24 a, 24 b, 24 c. The outer cover 18 helps to conform the bladder to thelimb for helping to evenly apply pressure for moving blood. For example,using the elasticity test described below, the outer cover 18 may havean average elasticity in the widthwise direction of between about 13lbs/in (23 N/cm) and about 15 lbs/in (26 N/cm), and in one embodimenthas an elasticity of about 13.6 lbs/in (23.8 N/cm). The outer cover 18may have an average elasticity in the longitudinally direction ofbetween about 19 lbs/in (33 N/cm) and about 22 lbs/in (39 N/cm), and inone embodiment an elasticity of about 19.8 lbs/in (34.7 N/cm).

The compression sleeve 10 as a whole is stretchable longitudinally byway of the longitudinally stretchable inner layer 12, intermediatelayers 14, 16 and outer cover 18. Further, the sleeve 10 is slightlystretchable widthwise by way of the abilities of the inner layer 12,intermediate layers 14, 16 and the cover 18 to stretch widthwise. Thewaterdrop-shaped openings 32 and the fact that the openings are offsetwidthwise also aid in the widthwise stretching.

It is common for patients that have undergone surgery to incur swellingof the limbs. The widthwise stretching of the sleeve 10 is morecomfortable for patients that experience swelling because the sleevewill stretch, i.e., increase in size circumferentially, as the limbswells. Moreover, elasticity of the sleeve 10 allows the wearer to havemore mobility of his or her limb and gives the practitioner a greaterdegree of freedom when wrapping the sleeve around a wearer's leg. Forexample, using the elasticity test described below, the thigh-lengthsleeve 10, comprising the inner layer 12, the intermediate layers 14, 16and the outer cover 18 as described above, may have an averageelasticity in the widthwise direction of between about 22 lbs/in (39N/cm) and about 27 lbs/in (47 N/cm), and in one embodiment an elasticityof about 24.3 lbs/in (42.6 N/cm). The compression sleeve 10 may have anaverage elasticity in the lengthwise direction of between about 17lbs/in (30 N/cm) and about 22 lbs/in (39 N/cm), and in one embodiment anelasticity of about 19.4 lbs/in (34.0 N/cm).

In another example, using the elasticity test described below, aknee-length sleeve, comprising an inner layer, intermediate layers andouter cover of the same material as the thigh-length sleeve describedabove, may have an average elasticity in the widthwise direction ofbetween about 22 lbs/in (39 N/cm) and about 27 lbs/in (47 N/cm), and anaverage elasticity in the lengthwise direction of between about 33lbs/in (58 N/cm) and about 40 lbs/in (70 N/cm).

The following test (herein referred to as the “elasticity test”) is usedto measure the elasticity of the layers 12, 14, 16 and 18 and the sleeve10, both widthwise and lengthwise. First, structure clamps are securedto the structure (e.g., one of the layers 12, 14, 16, and 18 or thesleeve 10) to be tested. When testing the lengthwise elasticity, thestructure clamps are secured to top and bottom edges of the structure.When testing the widthwise elasticity, the structure clamps are securedto opposite side edges of the structure. The sleeve sample with thestructure clamps secured thereto is placed in a universal tensiletesting machine (such as a universal testing machine manufactured byInstron® of Grove City, Pa.) by securing the structure clamps toopposing machine clamps of the machine. The machine should include amicroprocessor having a tensile force measurement program used tocontrol the machine and record measurements of force and displacement.Once the structure is secured in the machine, the opposing machineclamps are moved apart to a position that eliminates or minimizes theslack in the structure. This position is the initial position for allsubsequent tests. The tensile force measurement program is thenexecuted. The displacement of the sleeve sample as the machine clampsare moved apart should be uniform linear elongation and should notdamage the structure. This displacement is set and maintained for eachtest repetition. The test is repeated 7 times for each layer 12, 14, 16and 18 and the sleeve 10. Elasticity is calculated as force (lbs)divided by the displacement (in). An average elasticity of the 8 testsis calculated by summing the elasticity calculations for the 8 tests anddividing the sum by 8.

The sleeve in some embodiments is made more comfortable for the wearerby the fact that the inner layer 12 and the outer cover 18 are securedto the respective intermediate layers 14, 16 only adjacent to the outerperipheries of the inner layer and cover whereby the bladders 24 a, 24b, 24 c are not secure directly to the inner layer and cover. Thisconstruction allows for the bladders 24 a, 24 b, and 24 c to moveindependently of the inner layer 12, and vice versa. Co-assigned U.S.patent application Ser. No. 11/299,568 disclosing an embodiment directedto reducing chafing of a person's skin during use is incorporated hereinby reference.

Thus, when the sleeve 10 is wrapped circumferentially around thewearer's limb, the inner layer 12 substantially conforms to the contouror shape of the limb and will remain substantially stationary againstthe wearer's limb as the bladders 24 a, 24 b, 24 c inflate and deflateand/or shift positions. The movement of the bladders 24 a, 24 b, 24 cboth as they inflate and deflate and shift positions relative to thelimb may cause chafing and other discomfort for the patient if thesurface of the bladders continuously rubbed against the limb. However,by being secured only at the outer peripheries of the intermediatelayers 14, 16, the inner layer 12 creates a buffer between the bladders24 a, 24 b, 24 c and the limb that prevents chafing and other frictionagainst the skin of the limb. The bladders 24 a, 24 b, 24 c may movewithout causing corresponding movement of the inner layer 12 against theskin.

When introducing elements of the present invention or the preferredembodiment(s) thereof, the articles “a”, “an”, “the” and “said” areintended to mean that there are one or more of the elements. The terms“comprising”, “including” and “having” are intended to be inclusive andmean that there may be additional elements other than the listedelements.

As various changes could be made in the above constructions, products,and methods without departing from the scope of the invention, it isintended that all matter contained in the above description and shown inthe accompanying drawings shall be interpreted as illustrative and notin a limiting sense.

1. A device for applying compression treatment to a part of a wearer'sbody, the device comprising: first and second opposing bladder layerssecured to one another along two bladder lines to define first andsecond inflatable bladders spaced apart from one another along an axisof the device; a connecting section including a portion of at least oneof the first and second bladder layers extending between and connectingthe first and second inflatable bladders to one another; a line ofweakness in the connecting section extending generally transverse to theaxis of the device for selectively separating the inflatable bladdersfrom one another; an overlying layer in generally opposing relationshipto one of the first and second bladder layers, the overlying layer beingdiscontinuous generally adjacent to the line of weakness to defineterminal edge margins of the overlying layer extending generally alongthe line of weakness, the terminal edge margins each being connected toat least one of the first and second bladder layers on an opposite sideof the line of weakness from the other terminal edge margin.
 2. A deviceas set forth in claim 1 wherein the terminal edge margins are spacedapart from each other on opposite sides of the line of weakness.
 3. Adevice as set forth in claim 2 wherein the overlying layer includesseparate first and second overlying layer portions spaced axially apartfrom each other along a line extending transverse to the axis of thedevice.
 4. A device as set forth in claim 1 wherein the terminal edgemargins of the overlying layer are secured to said one of the first andsecond bladder layers along the terminal edge margins.
 5. A device asset forth in claim 4 further comprising a tube extending along theconnecting portion for delivering air to the first inflatable bladder,wherein each terminal edge margin secured to said one of the first andsecond bladder layers along a discontinuous weld line that does notextend across the tube.
 6. A device as set forth in claim 4 wherein theoverlying layer is further secured to said one of the first and secondbladder layers along perimeter securement lines running generallyadjacent to a perimeter of the overlying layer, wherein at least amajority portion of the overlying layer within the perimeter of theoverlying layer is free from securement to both the first and secondbladder layers.
 7. A device as set forth in claim 6 wherein theperimeter securement lines extend substantially continuously around theperiphery of the overlaying layer.
 8. A device as set forth in claim 1wherein the overlying layer comprises a breathable mesh fabric material.9. A device as set forth in claim 1 wherein the overlying layercomprises an inner liner in generally opposing relationship to the firstbladder layer.
 10. A device as set forth in claim 9 further comprisingan outer cover in generally opposing relationship to the second bladderlayer, the outer cover being discontinuous generally adjacent to theline of weakness to define terminal edge margins of the outer coverextending generally along the line of weakness, the terminal edgemargins each being connected to the second bladder layer on an oppositeside of the line of weakness from the other terminal edge margin.
 11. Adevice as set forth in claim 9 further comprising a tube extending alongthe connecting portion for delivering air to the first inflatablebladder, wherein each terminal edge margin is connected to the secondbladder layer along a discontinuous weld line that does not extendacross the tube.
 12. A device as set forth in claim 10 wherein theterminal edge margins of the outer cover are spaced apart from eachother on opposite sides of the line of weakness.
 13. A device as setforth in claim 12 wherein the outer cover includes separate first andsecond overlying layer portions spaced axially apart from each otheralong a line extending transverse to the axis of the device.
 14. Adevice as set forth in claim 12 wherein the terminal edge margins of theouter cover are secured to the second bladder layer along the terminaledge margins.
 15. A device as set forth in claim 1 wherein the line ofweakness comprises a perforation line.
 16. A device as set forth inclaim 15 wherein the connecting section comprises portions of both thefirst and second bladder layers, wherein the line of weakness comprisesperforation lines formed in both the first and second bladder layers.17. A device as set forth in claim 1 wherein the device includes a kneeopening sized and shaped to receive a knee of the wearer, the connectingportion comprising first and second bridge members on opposite sides ofthe knee opening extending from a distal section of the device thatincludes the second bladder to a proximal section of the device thatincludes the first bladder, wherein the line of weakness comprises afirst line of weakness generally adjacent to where the first bridgemember meets the distal section and a second line of weakness generallyadjacent to where the second bridge member meets the distal section. 18.A device as set forth in claim 16 further comprising: a first tube influid communication with the first bladder for delivering pressurizedfluid to the first bladder and a second tube in fluid communication withthe second bladder for delivering pressurized fluid to the secondbladder, the first tube extending across the first line of weakness andthrough the first bridge member between the first and second bladderlayers; and a tube access opening extending through the second bladderlayer in the first bridge member, a portion of the first tube beingaccessible through the tube access opening for withdrawing the firsttube through the opening.
 19. A device as set forth in claim 16 whereinthe overlying layer comprises an outer cover in generally opposingrelationship to the second bladder layer, wherein the tube accessopening extends through the outer cover.
 20. A method of making acompression device comprising: securing first and second opposingbladder layers to one another along two bladder lines to define firstand second inflatable bladders spaced apart from one another along anaxis of the device and having a connecting section extending between andconnecting the first and second inflatable bladders to one another;forming a line of weakness in the connecting section extending generallytransverse to the axis of the device for selectively separating theinflatable bladders from one another; securing an overlying layer ingenerally opposing relationship to one of the first and second bladderlayers, the overlying layer being discontinuous generally adjacent tothe line of weakness to define opposing terminal edge margins, whereineach of the terminal edge margins is secured to one of the first andsecond bladder layers on a respective opposite side of the line ofweakness.
 21. A method as set forth in claim 20 wherein said securing anoverlying layer comprises securing the terminal edge margins of theoverlying layer to said one of the first and second bladder layers atthe terminal edge margins along the line of weakness, and securing theoverlying layer to said one of the first and second bladder layers alonga perimeter of the overlying layer, wherein at least a majority portionof the overlying layer within the perimeter of the overlying layer isfree from securement to said one of the first and second bladder layers.22. A method as set forth in claim 21 wherein said securing an overlyinglayer comprises securing an inner liner in generally opposingrelationship to the first bladder layer, wherein the method furthercomprises securing an outer cover in generally opposing relationship tothe second bladder layer, the outer cover being discontinuous generallyadjacent to the line of weakness to define opposing terminal edgemargins of the outer cover, wherein each of the terminal edge margins ofthe outer cover is secured to the second bladder layer on a respectiveopposite side of the line of weakness.